Patent application title: LIQUID EJECTING APPARATUS

Abstract:

A liquid ejecting apparatus according to the invention includes a liquid
ejecting head capable of ejecting liquid from nozzle openings provided in
a nozzle-forming surface, a nozzle-forming-surface visual-inspection unit
for enabling a visual inspection of the nozzle-forming surface, and a
liquid receptacle for receiving liquid discharged as waste liquid from
the nozzle openings in the liquid ejecting head. The liquid receptacle is
movable between a receiving position, where the liquid receptacle is
positioned adjacent to the nozzle-forming surface, and a non-receiving
position, where the liquid receptacle is positioned away from the
receiving position. The liquid receptacle covers the
nozzle-forming-surface visual-inspection unit when the liquid receptacle
is positioned at the receiving position. The nozzle-forming-surface
visual-inspection unit allows the nozzle-forming surface to be visually
inspected when the liquid receptacle is positioned at the non-receiving
position.

Claims:

1. A liquid ejecting apparatus comprising:a liquid ejecting head capable
of ejecting liquid from nozzle openings provided in a nozzle-forming
surface of the liquid ejecting head;a nozzle-forming-surface
visual-inspection unit for enabling a visual inspection of the
nozzle-forming surface; anda liquid receptacle capable of receiving
liquid discharged as waste liquid from the nozzle openings in the liquid
ejecting head,wherein the liquid receptacle is capable of being moved
between a receiving position, where the liquid receptacle is positioned
adjacent to and facing the nozzle-forming surface so as to cover the
nozzle-forming-surface visual inspection unit, and a non-receiving
position, where the liquid receptacle is positioned away from the
receiving position so as to allow the nozzle-forming-surface
visual-inspection unit to enable visually inspection of the
nozzle-forming surface.

2. The liquid ejecting apparatus according to claim 1,wherein the liquid
receptacle is positioned below the nozzle-forming surface and away from
the liquid ejecting head when the liquid receptacle is positioned at the
non-receiving position, in a direction that is lateral to the
nozzle-forming surface.

3. The liquid ejecting apparatus according to claim 2,wherein the liquid
receptacle is positioned below the nozzle-forming surface and is oriented
perpendicularly or obliquely to the nozzle-forming surface when the
liquid receptacle is positioned at the non-receiving position.

4. The liquid ejecting apparatus according to claim 1,wherein the
nozzle-forming-surface visual-inspection unit includes a driving
mechanism for changing a field of view during the visual inspection of
the nozzle-forming surface.

5. The liquid ejecting apparatus according to claim 1,wherein the
nozzle-forming-surface visual-inspection unit includes a microscope for
taking an image of the nozzle-forming surface and outputting the image in
the form of an image signal, and a monitor for reproducing the image
signal as an image.

6. The liquid ejecting apparatus according to claim 1, wherein a plurality
of liquid ejecting heads are provided in the liquid ejecting apparatus.

7. A liquid ejecting apparatus comprising:a liquid ejecting head capable
of ejecting liquid from nozzle openings provided in a nozzle-forming
surface of the liquid ejecting head;a nozzle-forming-surface
visual-inspection unit for enabling a visual inspection of the
nozzle-forming surface; anda liquid receptacle capable of receiving
liquid discharged as waste liquid from the nozzle openings in the liquid
ejecting head and being moved between a receiving position where the
liquid receptacle is positioned below the nozzle-forming surface and a
non-receiving position where the liquid receptacle is positioned below
and perpendicular to the nozzle-forming surface;wherein the
nozzle-forming-surface visual-inspection unit is capable of enabling the
visual inspection of the nozzle-forming surface when the liquid
receptacle is in the non-receiving position.

8. The liquid ejecting apparatus according to claim 7,wherein the liquid
receptacle is positioned below the nozzle-forming surface and is oriented
perpendicularly or obliquely to the nozzle-forming surface when the
liquid receptacle is positioned at the non-receiving position.

8. The liquid ejecting apparatus according to claim 7,wherein the
nozzle-forming-surface visual-inspection unit includes a driving
mechanism for changing a field of view during the visual inspection of
the nozzle-forming surface.

9. The liquid ejecting apparatus according to claim 7,wherein the
nozzle-forming-surface visual-inspection unit includes a microscope for
taking an image of the nozzle-forming surface and outputting the image in
the form of an image signal, and a monitor for reproducing the image
signal as an image.

10. The liquid ejecting apparatus according to claim 7, wherein a
plurality of liquid ejecting heads are provided in the liquid ejecting
apparatus.

Description:

[0003]The present invention relates to a liquid ejecting apparatus. More
particularly, the present invention relates to a liquid ejecting
apparatus including a liquid ejecting head which is capable of ejecting
liquid from nozzle openings.

[0004]2. Related Art

[0005]Ink jet printers (hereinafter, referred to as "printers") are known
examples of liquid ejecting apparatuses which are capable of ejecting
liquid from a plurality of nozzles provided in a liquid ejecting head.
These printers typically have a maintenance unit for performing a variety
of maintenance operations to prevent and resolve any clogging in the
nozzles due to thickened ink.

[0006]One example of a maintenance currently used in the art is disclosed
in Japanese Patent No. JP-A-2003-154672, which describes a maintenance
unit having a vacuuming mechanism for vacuuming ink in a recording head,
which serves as a liquid ejecting head, and a wiper mechanism for wiping
the surface provided with nozzles (hereinafter, a "nozzle-forming
surface"). Other maintenance units currently known in the art are
equipped with a flushing box which receives ink discharged from nozzle
openings in accordance with a driving signal unrelated to printing.

[0007]When the variety of maintenance operations performed by the
maintenance units do not resolve a clogging in the recording head, the
recording head is removed from a printer body to so that a visual
inspection of the nozzle-forming surface may be performed. If the defect
in the recording head is determined is identified during the visual
inspection and subsequently fixed, the recording head is reattached to
the printer body. For example, when ink has been deposited near the
nozzles, the deposit is removed using a cotton bud soaked with a cleaning
liquid. If no resolvable defect is found during the visual inspection of
the recording head, the defect is deemed to be located inside the
recording head, and the recording head is replaced with a new recording
head.

[0008]One problem with this process, however, is that removing the
recording head to visually inspect the recording head for defects wastes
time because reattaching and repositioning the recording head to properly
attach the recording head to the printer is time-consuming work.

[0009]This situation occurs not only with the ink jet printers as
described above, but also with other liquid ejecting apparatuses having a
liquid ejecting head for ejecting liquid from nozzle openings.

BRIEF SUMMARY OF THE INVENTION

[0010]An advantage of some aspects of the invention is that it provides a
liquid ejecting apparatus that enables an inspection for determining the
cause of clogging of nozzle openings without needing to remove a liquid
ejecting head.

[0011]A liquid ejecting apparatus according to the invention includes a
liquid ejecting head for ejecting liquid from nozzle openings provided in
a nozzle-forming surface, a nozzle-forming-surface visual-inspection unit
for enabling a visual inspection of the nozzle-forming surface, and a
liquid receptacle for receiving liquid discharged as waste liquid from
the nozzle openings in the liquid ejecting head. The liquid receptacle is
movable between a receiving position, where the liquid receptacle is
positioned adjacent to and faces the nozzle-forming surface, and a
non-receiving position, where the liquid receptacle is positioned away
from the receiving position. The liquid receptacle covers the
nozzle-forming-surface visual-inspection unit when the liquid receptacle
is positioned at the receiving position. The nozzle-forming-surface
visual-inspection unit allows the nozzle-forming surface to be visually
inspected when the liquid receptacle is positioned at the non-receiving
position.

[0012]This structure uses the nozzle-forming-surface visual-inspection
unit to allow visual inspection of the nozzle-forming surface, whereby
the cause of clogging can be easily inspected without needing to remove
the liquid ejecting head from the liquid ejecting apparatus. Accordingly,
the time required for removing and reattaching a liquid ejecting head can
be saved. When the liquid receptacle is positioned at the receiving
position, the liquid receptacle covers the nozzle-forming-surface
visual-inspection unit. Because the liquid receptacle and the
nozzle-forming-surface visual-inspection unit overlap each other in the
direction perpendicular to the moving direction of the liquid receptacle,
the provision of the nozzle-forming-surface visual-inspection unit does
not increase the size of the liquid ejecting apparatus.

[0013]The positioning of a liquid ejecting head requires precision, and is
quite time-consuming work. In this configuration, because the liquid
ejecting head is provided in a plurality, the time required for removing
and reattaching the liquid ejecting head can be saved effectively.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]The invention will be described with reference to the accompanying
drawings, wherein like numbers reference like elements.

[0015]FIG. 1 is a perspective view of an ink jet printer according to one
embodiment of the present invention;

[0016]FIG. 2 is a bottom view of a recording head according to the
embodiment of the invention shown in FIG. 1;

[0017]FIG. 3 is a plan view of a portion of a maintenance unit;

[0018]FIG. 4 is a sectional view showing an engagement between a lead
screw and a tubular portion of a moving member; and

[0019]FIGS. 5A-5C are side views of the maintenance unit shown in FIG. 3.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0020]An ink jet printer (hereinafter referred to as a "printer")
according to one embodiment of the invention will now be described with
reference to FIGS. 1 to 5.

[0021]FIG. 1 illustrates a printer 11, which serves as a liquid ejecting
apparatus, according to one embodiment of the present invention. The
printer 11 has a substantially box-shaped body case 12. A platen 13
extends in the lengthwise direction along the bottom surface of the body
case 12, in a main scanning direction, shown as the left to right
direction in FIG. 1. The platen 13 serves as a stage for supporting
recording paper P, and feeds the recording paper P in the subscanning
direction (shown as the front to rear direction in FIG. 1) which is
perpendicular to the main scanning direction using a driving force from a
paper feed motor 14.

[0022]In the body case 12, a pole-like guide shaft 15 is disposed above
the platen 13. The guide shaft 15 supports a carriage 16 in a movable
manner. A driving pulley 17 and a driven pulley 18 are supported in a
rotatable manner on an inner surface of the body case 12 at positions
which correspond to each end of the guide shaft 15. A carriage motor 19,
which serves as a source of a driving force to reciprocate the carriage
16, is connected to the driving pulley 17. A timing belt 20 which
supports the carriage 16 runs over the pair of pulleys 17 and 18. Thus,
the carriage 16 is guided by the guide shaft 15 and driven by the
carriage motor 19, and is moved in the main scanning direction via the
timing belt 20.

[0023]Referring to FIG. 2, a plurality (three, in the present embodiment)
of recording heads 21, which serve as liquid ejecting heads, are provided
on the bottom surface of the carriage 16. The bottom surface of each
recording head 21 constitutes a nozzle-forming surface 21a, in which a
plurality of nozzle openings 22 are provided. As shown in FIG. 1, a
plurality (five, in the present embodiment) of ink cartridges 23 are
removably fitted in the carriage 16 for supplying the recording heads 21
with a liquid, such as ink. A printing process is performed by ejecting
ink stored in the ink cartridges 23 through the nozzle openings 22 onto
the recording paper P.

[0024]Maintenance units 24a and 24b, referred collectively as maintenance
units 42, are provided on both ends of the body case, and are used for
preventing and resolving clogging of the nozzle openings 22 caused by
thickened ink. In one embodiment of the present invention, the ends
(right and left ends in FIG. 1) of the body case 12 may be referred to as
non-printing regions where the recording paper P does not extend.

[0025]In one embodiment of the invention, the maintenance unit 24a
provided on the right side of the body case 12 shown in FIG. 1, includes
a cap member 25, a vacuum pump (not shown), and a wiper member 26.

[0026]The maintenance unit 24b provided on the opposite end (left end in
FIG. 1) of the body case 12 will be described with reference to FIGS. 3
to 5.

[0027]Referring to FIG. 3, the maintenance unit 24b includes a front frame
27 and a rear frame 28 supported by the body case 12 through brackets
(not shown). A driving motor 29 capable of bidirectional rotation is
attached to the front frame 27. A timing belt pulley (not shown) for
transmitting power is connected to the rear end of the output shaft 29a
of the driving motor 29.

[0028]Two parallel lead screws 30, which extend in a substantially
horizontal direction between the front frame 27 and the rear frame 28,
are provided so as to be separated from each other a predetermined
distance in the left-right direction. A timing belt pulley 31 is fitted
to the front end of each lead screw 30. An endless pinion belt 32 runs
over the timing belt pulleys 31 which are connected to the output shaft
29a of the driving motor 29. The lead screws 30 are rotatably supported
by the rear frame 28 at one end. As the driving motor 29 rotates to
generate a driving force, the lead screws 30 synchronously rotate in the
same direction about their shaft axes S.

[0029]The lead screws 30 are each fitted with a moving member 33. As shown
in FIG. 4, the moving member 33 has a tubular portion 33a that is engaged
with the lead screw 30. The tubular portion 33a has a hole 34, which
radially penetrates the tubular portion 33a, into which a pin 35 is
inserted. Inside the tubular portion 33a, the tip of the pin 35 is
engaged with a screw thread 36 formed on the outer peripheral surface of
each lead screw 30.

[0030]When the lead screws 30 are rotated, the screw threads 36 guide the
pins 35 engaged therewith, causing the moving members 33 to move
frontward and rearward along the shaft axes S of the lead screws 30 in a
synchronized manner.

[0031]In the present embodiment, when the driving motor 29 rotate in a
clockwise direction, the lead screws 30 rotate in the same clockwise
direction, causing the moving members 33 to move rearward from the front
frame 27 towards the rear frame 28. In contrast, when the driving motor
29 is reversed, and rotated in a counter-clockwise direction, the lead
screws 30 rotate in the reverse direction, causing the moving members 33
to move forward from the rear frame 28 toward the front frame 27.

[0032]As shown in FIG. 3, a supporting piece 37 is provided at the front
end of each moving member 33 so as to project frontward from the inside
of the tubular portion 33a. The supporting pieces 37 of the moving
members 33 support a pair of shafts 39, which are provided so as to
horizontally project from both the left and right surfaces of the rear
side of the flushing box 38, in a rotatable manner.

[0033]The flushing box 38 has an open box-shaped receiving portion 40
having a bottom surface where ink may be collected. When the carriage 16
is moved to the position above the maintenance unit 24b while the moving
members 33 are positioned as shown in FIG. 5A, the receiving portion 40
is positioned below the recording heads 21, with the opening thereof
closely facing the nozzle-forming surface 21a. That is, at this time, the
flushing box 38 is positioned at the receiving position where it can
receive ink discharged from the nozzle openings 22 in the recording heads
21. The receiving portion 40 contains an ink absorber 41 fixed to the
receiving portion 40 using a wire 42. The ink absorber 41 is capable of
absorbing and retaining discharged ink.

[0034]As shown in FIGS. 3 and 5, plate-like leg portions 43 are provided
so as to extend diagonally (in a diagonally frontward direction, in FIG.
5A) from both sides of the front end of the flushing box 38. Each leg
portion 43 has a cylindrical engaging projection 44 which projects
horizontally from the outer surface of the front tip for the leg portion
43 and a pin 45 which projects horizontally from the central portion of
the inner surface of the leg portion 43.

[0035]A stepped member 46 having a rectangular shape is disposed between
the front frame 27 and the rear frame 28, at a position near the front
frame 27. Both the left and right side walls of the stepped member 46
have a substantially trapezoidal shape as shown in FIGS. 5A to 5C, and
the top surfaces thereof constitute stepped portions 47 having a
predetermined width in the left to right direction as shown in FIG. 3.
The front upper corners of the stepped portions 47 are chamfered to form
inclined surfaces which extend diagonally downward. The left and right
stepped portions 47 are each provided with an engaging projection 48,
which is substantially L-shaped which projects frontward at the rear ends
thereof, and a pin 49 horizontally projecting from the inner surfaces
thereof.

[0036]Each pin 45 of the flushing box 38 is connected to the corresponding
pin 49 of the stepped member 46 through a coil spring 50. The coil
springs 50 exert a force on the flushing box 38 in the counterclockwise
direction in FIGS. 5A to 5C, using the shafts 39 as the fulcrum of
rotation. When the moving members 33 are positioned as shown in FIG. 5C,
the flushing box 38 is oriented perpendicularly with the opening of the
receiving portion 40 facing frontward, and the flushing box 38 is held at
the non-receiving position away from the receiving position.

[0037]The width of the flushing box 38 in the left-right direction is
designed such that when both the left and right leg portions 43 are
positioned on the stepped portions 47, the engaging projections 44 of the
leg portions 43 engage the engaging projections 48 of the stepped
portions 47, as shown in FIG. 5A, such that the receiving portion 40 is
positioned between the engaging projections 48, as shown in FIG. 3. This
allows the flushing box 38 to pass between the two engaging projections
48 of the stepped member 46 and over the stepped portions 47, and move in
the front-rear direction. Since the front upper portions of the stepped
portions 47 constitute inclined surfaces, the flushing box 38 smoothly
slides along the surfaces when it passes over the stepped portions 47, as
shown in FIG. 5B.

[0038]More specifically, when the moving members 33 are moved rearward
while the flushing box 38 is held at the non-receiving position as shown
in FIG. 5C under the urging force of the coil spring 50, both the left
and right ends of the bottom surface of the flushing box 38 contact the
stepped portions 47, so as to be oriented obliquely as shown in FIG. 5B.
Then, the flushing box 38 moves along with the moving members 33,
gradually changing its orientation from oblique to horizontal. Finally,
the flushing box 38 is oriented horizontally while the engaging
projections 44 are engaged with the engaging projections 48, and the leg
portions 43 are supported by the stepped portions 47, as shown in FIG.
5A.

[0039]Thus, the flushing box 38 is capable of moving from the receiving
position where the receiving portion 40 closely faces the nozzle-forming
surface 21a to the non-receiving position distant away from the receiving
position.

[0040]As shown in FIGS. 5A to 5C, a nozzle-forming-surface
visual-inspection unit 51 is disposed at a position between the front
frame and the rear frame 28, to the rear side of the stepped member 46,
that is below the receiving portion 40 when the flushing box 38 is
positioned at the receiving position as shown in FIG. 5A.

[0041]The nozzle-forming-surface visual-inspection unit 51 has a
microscope 52, and an X-Y table 53, which serves as a driving mechanism,
for supporting the microscope 52. The X-Y table 53 includes an X table
53a for moving the microscope 52 in the front-rear direction, and a Y
table 53b for moving the microscope 52 in the left-right direction. The
X-Y table 53 moves the microscope 52 in both the front-rear direction and
left-right direction to change the field of view of the microscope 52.
The X-Y table 53 is driven by a source of a driving force (not shown),
which is provided in addition to the driving motor 29.

[0042]The microscope 52 takes an image of the region above it, and outputs
the image in the form of an image signal. The image signal output from
the microscope 52 is reproduced on the monitor (not shown) provided on
the outer surface of the body case 12.

[0043]When the carriage 16 is moved to the position above the maintenance
unit 24b while the flushing box 38 is positioned at the non-receiving
position, as shown in FIG. 5C, the microscope 52 can take an image of the
nozzle-forming surface 21a. Thus, the nozzle-forming surface 21a can be
visually inspected through the monitor by reproducing the image taken by
the microscope 52 on the monitor. In contrast, while the flushing box 38
is positioned at the receiving position, as shown in FIG. 5A, the
flushing box 38 blocks the view of the nozzle-forming-surface
visual-inspection unit 51.

[0044]Operation of the maintenance units 24 having the above-described
structures will now be described.

[0045]When, for example, a discharge failure occurs when nozzles become
clogged by thickened ink during printing, a declogging process may be
performed as a maintenance operation, wherein ink from the recording
heads 21 is sucked and removed using the cap member 25 and a vacuum pump.

[0046]During this process, the carriage 16 is moved to the position above
the maintenance unit 24a. Then, the cap member 25 is moved upward and
brought into contact with the recording heads 21 so as to enclose the
nozzle openings 22. When the vacuum pump drives, the thickened ink in the
recording heads 21 is vacuumed and removed from the nozzle openings 22.

[0047]When ink is discharged from the nozzle openings 22 in the recording
heads 21 onto the recording paper P during printing, the ink droplets may
bounce back from the recording paper P and become deposited on the
nozzle-forming surface 21a. Such deposited ink may affect the direction
of ink discharge from the nozzle openings 22, and may cause a printing
failure. Therefore, wiping of the nozzle-forming surface 21a with a wiper
member 26 may be performed as a maintenance operation.

[0048]During this process, the carriage 16 is moved to the position above
the maintenance unit 24a. Then, the wiper member 26 is moved rearward and
brought into contact with the nozzle-forming surface 21a in a slidable
manner, in order to wipe off the deposited ink.

[0049]When, for example, ink is continuously discharged from specific
nozzle openings 22, ink in idle nozzles may thicken because of water
evaporation. Because thickened ink may cause a printing failure by
clogging the nozzle openings 22, a flushing process may be performed,
wherein ink is discharged as waste liquid from the nozzle openings 22 in
accordance with a driving signal unrelated to printing.

[0050]In this case, the carriage 16 is moved to the position above the
maintenance unit 24b. In the maintenance unit 24b, the flushing box 38 is
normally at the receiving position, as shown in FIG. 5A, during printing.
Therefore, when the nozzle openings 22 are caused to discharge ink while
the carriage 16 is at the region above the maintenance unit 24b, the
thickened ink is forcedly discharged from the recording heads 21 and is
received by the flushing box 38.

[0051]When performance of a variety of maintenance operations as described
above do not resolve the clogging of the nozzle openings 22, the nozzle
openings 22 may be inspected using the microscope 52 in order to visually
inspect the nozzle-forming surface 21a so as to determine the cause of
the clog or printing error.

[0052]In this case, the carriage 16 is moved to the position above the
maintenance unit 24b, as shown in FIG. 5A. Then, the driving motor 29 is
driven reversely to rotate the lead screws 30 in the direction of reverse
rotation. This causes the moving members 33 to move frontward, making the
flushing box 38, under the urging force of the coil spring 50, move
frontward along with the moving members 33 while gradually changing its
orientation from horizontal to oblique as shown in FIG. 5B. When the
moving members 33 are further moved frontward, the flushing box 38
finally is oriented perpendicularly as shown in FIG. 5C, and is held at
the non-receiving position by the urging force of the coil spring 50.

[0053]In this state, the microscope 52 can take an image of the
nozzle-forming surface 21a. The microscope 52 takes an image of the
nozzle-forming surface 21a, while changing the field of view using the
X-Y table 53. The cause of the clogging of the nozzle openings 22 can be
inspected by visually inspecting the nozzle-forming surface 21a through
the image reproduced on a monitor.

[0054]As a result of the visual inspection, if, for example, the presence
of a foreign substance, congealed ink, or the like attached to the
nozzle-forming surface 21a is confirmed, maintenance such as cleaning of
the nozzle-forming surface 21a is performed while the image of the
nozzle-forming surface 21a is shown on the monitor. A linear deposit of
ink on the nozzle-forming surface 21a indicates that the wiper member 26
is cracked. In that case, the wiper member 26 is replaced.

[0055]According to the above-described embodiment, the following
advantages can be achieved.

[0056]1. In the above-described embodiment, the cause of clogging of
nozzle openings 22 can be easily inspected without needing to remove the
recording heads 21 from the printer 11 by visually inspecting the
nozzle-forming surface 21a with the microscope 52. Thus, the time
required for removing and reattaching the recording heads 21 can be
saved.

[0057]2. In the above-described embodiment, when the flushing box 38 is
positioned at the receiving position, the flushing box 38 covers the
nozzle-forming-surface visual-inspection unit 51. That is, the flushing
box 38 and the nozzle-forming-surface visual-inspection unit 51 overlap
each other in the perpendicular direction. Accordingly, the provision of
the nozzle-forming-surface visual-inspection unit 51 does not increase
the size of the liquid ejecting apparatus.

[0058]3. In the above-described embodiment, because the flushing box 38
covers the nozzle-forming-surface visual-inspection unit 51 during
printing, ink mist is prevented from depositing on the
nozzle-forming-surface visual-inspection unit 51 during printing or
flushing.

[0059]4. In the above-described embodiment, the flushing box 38 is
oriented perpendicularly at the non-receiving position. This creates a
space between the recording heads 21 and the flushing box 38, which
allows a member, such as a cotton bud, to be inserted for cleaning the
recording heads 21.

[0060]5. In the above-described embodiment, the X-Y table 53 is capable of
changing the field of view during visual inspection of the nozzle-forming
surface 21a. Therefore, a desired area of the nozzle-forming surface 21a
can be visually inspected.

[0061]6. In the above-described embodiment, because the microscope 52
enables visual inspection of the nozzle-forming surface 21a with a
magnified image thereof, the fine nozzle openings 22 and the presence of
a deposited substance can be visually inspected. The microscope 52
outputs an image it took in the form of an image signal. Thus, by
providing the monitor for reproducing the image signal as an image on the
external surface of the body case 12, visual inspection of the
nozzle-forming surface 21a can be easily performed from the outside, and
there is no need to open the body case 12 to perform an inspection.
Further, by making the monitor show the image of the nozzle-forming
surface 21a taken by the microscope 52, maintenance such as cleaning can
be performed while visually inspecting the condition of the
nozzle-forming surface 21a.

[0062]7. The positioning of a recording head requires precision, and can
be quite time-consuming work. In the above-described embodiment, because
a plurality of recording heads 21 are provided, the time required for
removing and reattaching the recording head can be saved effectively.

[0063]The above-described embodiment may be modified into other
embodiments as follows.

[0064]In the above-described embodiment, the mechanism for moving the
flushing box 38 is not limited to the mechanism using the lead screws 30,
and may be a mechanism using a rack and pinion or a lever, for example.

[0065]In the above-described embodiment, the flushing box 38 need not be
oriented perpendicular to the nozzle-forming surface 21a when it is
positioned at the non-receiving position. It may be oriented, for
example, obliquely below the nozzle-forming surface 21a. Further, the
flushing box 38 may be oriented horizontally at a position below the
nozzle-forming surface 21a and away from the recording heads 21 in a
lateral direction in which the nozzle-forming surface 21a extends when it
is positioned at the non-receiving position, as long as a space is
maintained between the flushing box 38 and the recording heads 21.

[0066]In the above-described embodiment, the nozzle-forming-surface
visual-inspection unit 51 may have a mirror or a camera, instead of the
microscope 52. When the nozzle-forming surface 21a is reflected in a
mirror, for example, the body case 12 may be provided with a cover on the
front surface thereof, which may be opened to allow visual inspection of
the nozzle-forming surface 21a reflected in the mirror. When a camera
takes an image of the nozzle-forming surface 21a, the image may be
printed by the printer 11. When the nozzle-forming surface 21a is
visually inspected using a mirror or a camera, a monitor for reproducing
the image is not required.

[0067]In the above-described embodiment, the image taken by the microscope
52 may be reproduced on a monitor of a computer or the like, connected to
the printer 11.

[0068]In the above-described embodiment, a picture recorder for recording
the image taken by the microscope 52 may be used.

[0069]In the above-described embodiment, the nozzle-forming-surface
visual-inspection unit 51 or the printer 11 may have a lighting unit for
illuminating the nozzle-forming surface 21a.

[0070]In the above-described embodiment, the number of the recording heads
21 is not limited to three, and it may be one or another number other
than three. When two or more recording heads 21 are provided, they are
not necessarily arranged in a staggered formation as shown in the
above-described embodiment, and they may be arranged in any formation.

[0071]In the above-described embodiment, the driving mechanism for
changing the field of view of the microscope 52 is not limited to the X-Y
table 53 for moving the microscope 52. A rack and pinion or a piston, for
example, may be used to move the microscope 52. Alternatively, the field
of view of the microscope 52 may be changed by rotating the microscope
52, by changing the magnification of the microscope 52, or by providing a
plurality of microscopes having different magnifications, whose positions
are changeable.

[0072]In the above-described embodiment, the X-Y table 53 may not be
included. When the X-Y table 53 is not included, the microscope 52 may
take an image of the entire nozzle-forming surface 21a. Alternatively,
the microscope 52 may be provided in a plurality to increase the area
being inspected. When the microscope 52 is provided in a plurality, they
may be moved either simultaneously or individually.

[0073]In the above-described embodiment, the liquid ejecting apparatus may
be embodied as a so-called line head printer, whose recording head has a
size equivalent to the length of the recording paper P in the width
direction (left-right direction). Because a printer of this type does not
require the carriage to move in the main scanning direction, it may be
configured such that the microscope 52 is moved by the driving mechanism
in the top-bottom direction, the left-right direction, and the front-rear
direction.

[0074]Although the liquid ejecting apparatus is embodied as an ink jet
recording apparatus in the above-described embodiment, it may be embodied
as a liquid ejecting apparatus capable of ejecting or discharging a
liquid other than ink, including a liquid, a liquid containing particles
of a functional material dispersed or mixed therein, a flowable material
such as gel, and a solid material that can be flowed or ejected as
liquid. The liquid ejecting apparatus may also be embodied as: a liquid
ejecting apparatus capable of ejecting a liquid containing a material,
such as an electrode material or a color material (pixel material),
dispersed therein or dissolved therein; a liquid ejecting apparatus
capable of manufacturing liquid crystal displays, electroluminescence
(EL) displays, or surface emitting displays; a liquid ejecting apparatus
capable of ejecting a living organic material, used for manufacturing
biochips; a liquid ejecting apparatus capable of being used as a
precision pipette, for ejecting a liquid serving as a sample; a liquid
ejecting apparatus capable of ejecting lubricant onto a precision
instrument, such as a clock or a camera, with a pinpoint accuracy; a
liquid ejecting apparatus capable of ejecting a transparent liquid resin,
such as an ultraviolet curable resin, onto a substrate, for fabricating
hemispherical microlenses (optical lenses) usable in optical
communication elements; a liquid ejecting apparatus capable of ejecting
an acid or alkaline etchant to perform etching on a substrate; a
flowable-material ejecting apparatus capable of ejecting a flowable
material such as gel (for example, physical gel); and a powder or
granular material ejecting apparatus (for example, a toner jet recording
apparatus) capable of ejecting a solid, such as powder and granular
material, e.g., toner. The invention can be applied to any of the
above-described liquid ejecting apparatuses. As used herein, the term
"liquid" refers to a substance excluding a liquid consisting exclusively
of gas, and refers to a substance including, for example, liquid
(including inorganic solvent, organic solvent, solution, liquid resin,
and liquid metal (molten metal)), flowable material, powder, and granular
material.